2 files changed, 61 insertions, 36 deletions

diff --git a/src/lib/libc/string/strsep.3 b/src/lib/libc/string/strsep.3
index 0cae3e0f1b..471e693ecc 100644
--- a/src/lib/libc/string/strsep.3
+++ b/src/lib/libc/string/strsep.3
@@ -1,8 +1,11 @@
-.\" Copyright (c) 1990, 1991 The Regents of the University of California.
-.\" All rights reserved.
+.\" $OpenBSD: strsep.3,v 1.3 1997/08/20 04:28:13 millert Exp $
+.\"
+.\" Copyright (c) 1990, 1991, 1993
+.\"     The Regents of the University of California.  All rights reserved.
 .\"
 .\" This code is derived from software contributed to Berkeley by
 .\" Chris Torek.
+.\"
 .\" Redistribution and use in source and binary forms, with or without
 .\" modification, are permitted provided that the following conditions
 .\" are met:
@@ -31,9 +34,9 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     $OpenBSD: strsep.3,v 1.2 1996/08/19 08:34:24 tholo Exp $
+.\"     @(#)strsep.3    8.1 (Berkeley) 6/9/93
 .\"
-.Dd April 19, 1991
+.Dd June 9, 1993
 .Dt STRSEP 3
 .Os
 .Sh NAME
@@ -46,23 +49,29 @@
 .Sh DESCRIPTION
 The
 .Fn strsep
-locates in the null-terminated string at
-.Fa *stringp
-the first occurrence of any character in
-.Fa delim
-and replaces this with a
-.Ql \e0 ,
-records the location of the immediate following character in
+function locates, in the string referenced by
 .Fa *stringp ,
-then returns the original value of
+the first occurrence of any character in the string
+.Fa delim
+(or the terminating
+.Ql \e0
+character) and replaces it with a
+.Ql \e0 .
+The location of the next character after the delimiter character
+(or NULL, if the end of the string was reached) is stored in
 .Fa *stringp .
-If no delimiter characters are found,
-.Fn strsep
-sets
+The original value of
+.Fa *stringp
+is returned.
+.Pp
+An ``empty'' field, i.e. one caused by two adjacent delimiter characters,
+can be detected by comparing the location referenced by the pointer returned
+in
 .Fa *stringp
 to
-.Dv NULL ;
-if
+.Ql \e0 .
+.Pp
+If
 .Fa *stringp
 is initially
 .Dv NULL ,
@@ -72,20 +81,29 @@ returns
 .Sh EXAMPLES
 The following uses
 .Fn strsep
-to parse strings containing runs of white space,
-making up an argument vector:
+to parse a string, containing tokens delimited by white space, into an
+argument vector:
 .Bd -literal -offset indent
-char inputstring[100];
-char **argv[51], **ap = argv, *p, *val;
-/* set up inputstring */
-for (p = inputstring; p != NULL; ) {
-        while ((val = strsep(&p, " \et")) != NULL && *val == '\e0');
-        *ap++ = val;
-}
-*ap = 0;
+char **ap, *argv[10], *inputstring;
+
+for (ap = argv; (*ap = strsep(&inputstring, " \et")) != NULL;)
+        if (**ap != '\e0')
+                ++ap;
 .Ed
 .Sh HISTORY
 The
 .Fn strsep
-function is
-.Ud .
+function
+is intended as a replacement for the
+.Fn strtok
+function.
+While the
+.Fn strtok
+function should be preferred for portability reasons (it conforms to
+.St -ansiC )
+it is unable to handle empty fields, i.e. detect fields delimited by
+two adjacent delimiter characters, or to be used for more than a single
+string at a time.
+The
+.Fn strsep
+function first appeared in 4.4BSD.
diff --git a/src/lib/libc/string/strsep.c b/src/lib/libc/string/strsep.c
index 09f187b62d..b69b715fc5 100644
--- a/src/lib/libc/string/strsep.c
+++ b/src/lib/libc/string/strsep.c
@@ -1,6 +1,8 @@
+/*      $OpenBSD: strsep.c,v 1.3 1997/08/20 04:28:14 millert Exp $      */
+
 /*-
- * Copyright (c) 1990 The Regents of the University of California.
- * All rights reserved.
+ * Copyright (c) 1990, 1993
+ *      The Regents of the University of California.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -31,14 +33,19 @@
  * SUCH DAMAGE.
  */
 
+#include <string.h>
+#include <stdio.h>
+
 #if defined(LIBC_SCCS) && !defined(lint)
-static char *rcsid = "$OpenBSD: strsep.c,v 1.2 1996/08/19 08:34:24 tholo Exp $";
+#if 0
+static char sccsid[] = "@(#)strsep.c    8.1 (Berkeley) 6/4/93";
+#else
+static char *rcsid = "$OpenBSD: strsep.c,v 1.3 1997/08/20 04:28:14 millert Exp $";
+#endif
 #endif /* LIBC_SCCS and not lint */
 
-#include <string.h>
-
 /*
- * Get next token from string *stringp, where tokens are nonempty
+ * Get next token from string *stringp, where tokens are possibly-empty
  * strings separated by characters from delim.  
  *
  * Writes NULs into the string at *stringp to end tokens.
@@ -46,7 +53,7 @@ static char *rcsid = "$OpenBSD: strsep.c,v 1.2 1996/08/19 08:34:24 tholo Exp $";
  * On return, *stringp points past the last NUL written (if there might
  * be further tokens), or is NULL (if there are definitely no more tokens).
  *
- * If *stringp is NULL, strtoken returns NULL.
+ * If *stringp is NULL, strsep returns NULL.
  */
 char *
 strsep(stringp, delim)